Burn smell in car when using ac or heat, what could it be? on 1998 Toyota Avalon

I have replaced the seals in front of engine but not behind it. Don't see oil leakage, but the smell is terrible when I have heat or air on. I don't seem to get odor when heat/ac not in use.

by in Potwin, KS on January 13, 2014
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1 answer 1 comment
ANSWER by , January 13, 2014
poss exh leak,have a muffler shop ck for you
COMMENT by , May 04, 2014
See if oil is seeping from the valve cover on to the exhaust manifold.